This example describes installing a six node cluster spanning two racks in a single
data center. Each node is configured to use the RackInferringSnitch (multiple rack
aware) and 256 virtual nodes (vnodes). It is recommended to have more than one
seed node per data center.

In Cassandra, the term data center is a grouping of nodes. Data
center is synonymous with replication group, that is, a grouping of nodes configured
together for replication purposes.¶